18-wheeler vs truck and trailer

18-wheeler

noun
  • A big rig truck: a semi-trailer plus the truck or tractor pulling it. 

truck and trailer

noun
  • The situation where the ball carrier leaves a maul and is followed by teammates. 

  • The situation where one player skates directly behind a teammate and holds onto their hips in order to pivot. 

How often have the words 18-wheeler and truck and trailer occurred in a corpus of books? (source: Google Ngram Viewer )